Animal restraints such as leashes or tie-outs for animals, such as dogs, have been designed using fixed length leads, variable length leads, and leads which combine the function of both fixed length and variable length. Fixed length leads are problematic when the pet isn't far enough away from the pet owner or a fixed location, resulting in a leash which is loose, not taut, between the end attached to the animal and the opposite end held by the pet owner or attached to a fixed location. The loose lead can get tangled easily around the pet, pet owner or the fixed location. Variable length leashes and tie-outs, often in the form of retractable leashes, are designed with a leash wrapped around a spool within a casing which has a tension spring to allow the leash to extend out from or retract into the casing holding the spool as the pet either moves away from the pet owner or toward the pet owner, thus preventing slack in the leash. Retractable leashes allow for longer length extension than fixed length leashes. Retractable leashes typically have a brake, which, when engaged at a desired length less than full extension capability, prevents further length extension. The engaged brake typically results in a fixed length leash and the aforementioned functional deficiencies. There might be situations related to the size and temperament of the dog, the size and strength of the dog walker, and the safety conditions of the environment, where it is desirable to have a retractable leash which can extend and retract freely up to a length which is less than the full extended length of the leash.
To address the above problem, some retractable leash devices have attempted to provide brake actuating designs with maximum length settings less than full leash extension in order to offer retraction capability for leash lengths less than full leash extension.
All in all, these devices have major disadvantages. Some designs have setting limitation which don't accommodate practical application. Some designs are clumsy in that they require multi-step actuation or two-hand actuation. Another design is cumbersome in that it requires the dog to extend the leash to the desired maximum length and be stopped before the new extension maximum length can be set. In other designs, once the new maximum length has engaged the brake to prevent further extension, the setting can't be changed, if desired, to a new setting to accommodate a changing situation because the brake locks up the system. In one type of device, either the dog or the pet owner need to create slack in the leash in order to unlock the setting. This might require the pet owner using the manual brake as a second step. In addition to these limitations, many of these aforementioned designs have structural challenges where is not seen that they can be practically overcome.
Additional challenges relates to handle formation for a safe and comfortable grip. Other leash designs have non-adjustable grips which cannot accommodate varied hand sizes. Some attempts to remedy this include various fixed contour handles, but this one size fits all approach does not work.
Pet owners like to carry a variety of accessories, such as toys, to treats, water and clean-up devices, when walking a pet. Attempts to facilitate carry along convenience has been limited to hook-on systems which do not affix contents in a rigid manner. The loose nature of these devices affect both comfort and control.
When retractable leashes are in the mode of rapid extension which turns the leash spool inside the housing a rapid rate, actuating the brake can be problematic because the brake tooth has trouble engaging the turning spool. This problem affects both comfort and control since the brake does not engage immediately and the vibration from lack of engagement is uncomfortable and startling.
When retractable lashes are fully extended and a large force is encountered at the point of full extension, leashes frequently brake because they are designed with a stress point where the leash attaches to the spool or other interior positions. This problem is a safety issue because a broken leash results in a run-away pet.